I agree that they aren't a perfect replacement for coal fired, but there is still plenty of use for them.
For example, down in Arizona there is a ton, a ton, of land that has no use, just arid crap desert that is a billion degrees from pretty and would not be hurt at all to have a solar plant, especially the smaller solar thermal variety. We had something in the range of 8 billion sunny days a year if memory serves. Even if it is just to help push the technology along it doesn't hurt. Mind you, Southern Arizona doesn't have oil, or coal, or water for hydroelectric or farming, but it does have sun and wind, might as well use it.